The side of a building on one side of the street was also damaged by the flames.

Passers-by stood watching as the wreckage burned. A motorcycle was also lying on its side in the road where it was abandoned.

Fire and rescue services said they had taken “lots of emergency calls” as eyewitnesses described seeing grey smoke towering into the sky, close to Battersea Bridge, in Vauxhall.

A Met police spokesman said: “We had a call at approximately 8am this morning and we are dealing with an incident."

Rugby star Gareth Thomas said the helicopter crashed just metres from his London home.

The former Wales player, who is currently filming ITV reality show Dancing on Ice, told his Twitter followers: “OMG!!! In car on way to skating and just hearing the helicopter has crashed metres from my home!! Hope everyone in the area is ok.x”

Many eyewitnesses took to Twitter to report details.

One said the helicopter appeared to have hit a crane.

Another said it crashed close to a railway line.

One user posted a dramatic photograph showing burning wreckage in the road.

London Fire Brigade said on Twitter: “We’re attending reports of a helicopter crash near Wandsworth Road in South Lambeth.”

Commuter Sherna Noah described seeing a “large plume of dark grey smoke” as she crossed Battersea Bridge at around 8am.

She said: “I was coming across the bridge and basically I could see a few cyclists on the bridge looking towards the water.

“I looked over to see what they were looking at and could see a pall of grey smoke coming from the south side.

“You could see a large plume of dark grey smoke.”

A woman who answered the phone at the London Heliport, in Battersea, would not comment on the fire.

It is thought the helicopter may have hit two cars.

Passers-by stood watching as the wreckage burned.

As rush-hour traffic built up, the A3036 Wandsworth Road in Vauxhall was closed in both directions between Vauxhall Cross and the Lansdowne Way junction.

People took to Twitter to report gridlocked traffic in the area, with emergency services struggling to get through.

The First Capital Connect train company warned its passengers to expect travel difficulties in the Vauxhall area, although its services were not affected.

Flying conditions on Wednesday morning were reflected in the fact that London City Airport in Docklands had delays due to poor visibility.

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